class_docstr: class for handling plain text corpus
      
docstr: load plaintext folder to documents and apply unicode transformer
  
  :param str folder: path to directory
  :type folder: string
docstr_tok: ["load","plaintext","folder","to","documents","and","apply","unicode","transformer",":","param","str","folder",":","path","to","directory",":","type","folder",":","string"]
code: def load(self, folder):
      """load plaintext folder to documents and apply unicode transformer
  
      :param str folder: path to directory
      :type folder: string
      """
      ids = listdir(folder)
      files = [join(folder, f) for f in ids]
      contents = []
      for file in files:
          with io.open(file, "r", encoding="utf-8") as f:
              contents.append(f.read())
      documents = []
  
      for id, content in zip(ids, contents):
          document = Document(id)
          sentences = content.split("\n")
          unicode_transformer = UnicodeTransformer()
          sentences = [
              unicode_transformer.transform(sentence)
              for sentence in sentences
          ]
          document.set_sentences(sentences)
          documents.append(document)
      self.documents = documents
  
file_path: underthesea/underthesea/corpus/plaintext_corpus.py
imports: from underthesea.corpus import Corpus, Document
  from os.path import join
  from os import listdir, mkdir
  from underthesea.feature_engineering.unicode import UnicodeTransformer
  from underthesea.util.file_io import write
  import io
label_desc: Use image node_id 2 for calling the PlainTextCorpus obj's underlying member method code with example usage: obj.load(folder) without return types